# PSYC 1010 Study Guide - Standard Deviation, Statistical Hypothesis Testing, Test Statistic

by OC103274

Chapter 7

Raw Scores, z Scores, and Percentages

Step 1: convert raw score to z score

Step 2: look up area in Table B1

when you look up a number in the table in the % part it tells you the *area between mean and z*

-the table presents area between the mean and z and beyond the mean and z

To convert to a Raw Score

-if the population mean is 500 and the standard deviation is 100 and the z is 0.33 (or 63rd % tile)

x=z(SD) + population mean

x= 0.33 (100) + 500

= 33+500 =533

Z Table and Means

-need to calculate standard error because variability is smaller for distribution of means than for

distribution of scores

example:

A sample with N=36 has a mean = 533 from a population with a mean = 500 and standard

deviation = 100

whats the z score?

-standard error = 100/6 (square root of N) = 16.67

-z = (533-500) / 16.67 = 33/16.67 = 1.98

-percentile is 97.61(47.61 between 0 and z score – saw this on the table)

Parametric v. Nonparametric Tests

parametric tests: inferential statistical test based on assumptions about a population

(making assumptions about distribution)

nonparametric tests: inferential statistical test not based on assumptions about the population

(distribution free tests) – ranked ordinal data rather than calculating means

3 key assumptions for the z test

1. Dependent variable is a scale measure or variable

2. Participants have to be randomly selected

3. Population distribution is approximately normal (okay if the sample sizes are 30 or more)

6 Steps of Hypothesis Testing

1. Identify populations, distribution, and assumptions and then choose the appropriate

hypothesis test

2. State the null and research hypothesis in both words and symbolic notation

3. Determine the characteristics of the comparison distribution

4. Determine the critical values, or cutoffs, that indicate the points beyond which we will reject

the null hypothesis **most important step**

5. Calculate the test statistic

6. Decide whether to reject or fail to reject the null hypothesis

The z Test

-when we know the population mean and the standard deviation

-the z test:

one-tailed:

Two-tailed:

Do Questions in Textbook – chapter 7

7.29

7.35

7.39

7.45(a)

7.47

**Unlock Document**

## More from OC103274

###### PSYC 1010 Study Guide - Final Guide: Type I And Type Ii Errors, Central Limit Theorem, Confidence Interval

Exam Note

###### PSYC 1010 Lecture Notes - Pareto Chart, Nominal Category, Stroop Effect

Lecture Note

## Similar documents like this

###### PSYC 1010 Chapter Notes - Chapter 12: Null Hypothesis, F-Distribution, Analysis Of Variance

Textbook Note

###### PSYC 1010 Study Guide - Midterm Guide: Type I And Type Ii Errors, Statistical Power, Null Hypothesis

Exam Note

###### PSYC 1010 Lecture 8: PSYC1010 Jan 27

Lecture Note

###### PSYC1010 Lecture 8: Chapter 4: Correlation

Lecture Note

###### PSYC 1010 Lecture Notes - Lecture 3: Numerical Range, Central Tendency

Lecture Note

###### PSYC 1010 Lecture Notes - Lecture 19: Egg Cell, Psych, Cist

Lecture Note

###### PSYC 1010 Lecture Notes - Lecture 4: Western Water Catchment, Unimodality

Lecture Note

###### PSYC1010 Lecture 13: Chapter 5: Lecture Notes

Lecture Note

###### PSYC1010 Lecture 4: Chapter 3: Standardized Scores

Lecture Note

###### PSYC 1010 Lecture Notes - Lecture 2: Squared Deviations From The Mean, Kurtosis, Xm Satellite Radio

Lecture Note

###### PSYC 1010 Study Guide - Midterm Guide: Null Hypothesis, Statistical Hypothesis Testing, Standard Error

Exam Note

###### PSYC 1010 Lecture Notes - Lecture 3: Gambling, Xm Satellite Radio, Central Tendency

Lecture Note

###### PSYC 1010 Lecture Notes - Lecture 14: Glossary Of Riemannian And Metric Geometry, Mudita, Pluralistic Ignorance

Lecture Note

###### PSYC 1010 Lecture Notes - Pareto Chart, Nominal Category, Stroop Effect

Lecture Note

###### PSYC 1010 Final: stats final review (psych1010)

Exam Note